What app for reviewing and culling on Mac?

I am still an Aperture user. However, I do not like to import all my photos first and then start culling them. Often times I never get back to it and then I have a bloated Aperture library full of pics I will never use and probably would have deleted had I gone through that process before importing.

But, I am not happy with the native Finder or PathFinder for quickly reviewing the photos and deleting the bad, keeping the good, etc.

Please recommend some applications that are very well suited for this step of the workflow. I would like something that can work directly with photos in the file system without having to import them to its own library file. Something that makes it easy to go through and choose "yay or nay."

For my initial review, I just use Preview, which comes with OS X. Select 20 jpegs at a time (I shoot RAW+JPG), review them and delete those I don't want. Can do that directly from Preview. It's not the quickest way, but every Mac has this app.

As an Aperture user I have a couple of pointers that may ease the workflow without extra software

1) the way I work is that my images are not stored in the Aperture library... but are stored in the Pictures folder or indeed in any folder/drive I want... This is referred to a referenced library as opposed to a managed library. I am jet lagged to hell in Atlanta at the moment 16 hours into 24 hours of flying from Maui to Brussels, so I will let you google for more details on this

2) As soon as I import, I quickly go through al the images and press the 9 key to mark the obviously bad shots as rejected, and press the 5 key to mark the keepers or potential keeper Once I have done that I can view just the rejected shots and delete them. Deleting in Aperture only deletes them to the dedicated Aperture Trash , you have to explicitly empty that trash to the system trash before they are gone forever. The other day I came back from shooting surfers with 350 shots.. within say half an hour of getting to my computer I had rejected half the shot and focussed in about 30 keepers.

3) Pressing the P key when viewing photos shows only the embedded JPEG and allows for much faster loading of an image to allow you to mark them up.

I am going to miss Aperture when it finally is not supported, but so far it seems fine under El Capitan in general use.. so I will keep hanging in there